Artificial-tooth facing and backing therefor.



G. HOLTZ-- ARTIFICIAL TOOTH FACING AND BACKING THEREFOR.

A P P L I C A T l 0 N F l L E D l A N I 6 l 9 l 5- 1,157,309. Patented 001. 19, 1915.

WITNESSES 1 I Wm GUSTAV HOLTZ, OF GOULDSBORO, PENNSYLVANIA.

ARTIFICIAL-TOOTH FACING AND BACKING THEREFOR.

Specification of Letters Patent.

Application filed January 16, 1915. Serial No. 2,691.

To all whom it may concern:

Be it known that I, GUSTAV HoLTz, a citizen of the United States, residing at Gouldsboro, in the county of Wayne and State of Pennsylvania, have invented a new and useful Artificial-Tooth Facing and Backing Therefor, of which the following is a specification.

This invention has reference to backings for artificial tooth facings adaptable for either regulation or casting purposes.

The object of the present invention is to provide a backing which: will enable any dentist to produce his 'own backings, and which backings provide for interchangeability of the facings, thus permitting repairs to bridge work at low cost and without undue delay.

In accordance with the present invention the backing is designed to be used in connection with a tooth facing having the rear face inset to form a shoulder near to but spaced from the biting edge of the facing and the usual anchoring channel for the backing is continued into the body of the facing toward the biting edge to provide an anchoring end for an extension of an anchoring rib on the backing.

The backing of the present invention stops short of the biting edge of the tooth facing in an angle flange adapted to be seated against the shoulder formed in the rear face of the facing by the inset of such rear face and the backing is also provided with an anchoring rib having a prolongation to enter the continuation of the anchoring channel for the backing, which continuation enters the body of the tooth facing for a distance toward the biting edge. Theshoulder and flange coact to effectively resist forces such as are exerted in biting and which forces tend to move the facing lengthwise of the backing, while the elongation of the rib entering the body of the tooth facing resists forces tending to draw the facing laterally away from the backing.

The invention will be best understood from a consideration of the following dethe showing of the drawings, but may be changed and modified so long as such changes and modifications mark no material departure from the salient features of the invention.

In the drawings :-Figure 1 is a perspective view of a blank from which the backing may be formed. Figs. 2 to 6 are perspective views illustrating difierent steps in the formation of the backing. Fig. 7 is an edge elevation of the completed backing. Fig. 8 is a longitudinal section of a tooth facing with the backing applied. Fig. 9 is a section on the line 99 of Fig. 8. Fig: 10 is a perspective view as seen from the rear of the tooth facing and applied backing of Fig. 8.

Referring first to Figs. 8, 9 and 10, there is shown a tooth facing 1 having a biting edge 2 and an inset rear face 3 of less length than the body of the facing and terminating at a distance from the biting edge 2 in a lateral shoulder 4 which extends all the way across the tooth facing. Extending lengthwise of the body of the tooth facing 1 is a channel 5 shown in the drawings as of circular cross-section although it may have other shapes, and this channel communicates Patented Oct. 19, 1915.

along one long side with an elongated radial passage 6 opening through the rear face 3 of the tooth facing. The channel 5 has a continuation 7 entering the body of the tooth facing beyond the shoulder 4 toward the biting edge 2 for a purpose which will hereinafter appear.

In accordance with the present invention there is provided a backing 8 of a length corresponding to the inset rear face 3 of the tooth facing, and at one end this backing has an angularly ofiset flange -9 corresponding to the shoulder 4. On that face of the backing remote from the flange 9 it is formed with a central longitudinal rib 1O joining the body ofthe plate by a corresponding neck 11 elongated in the direction of the length of the rib. That end of the rib adjacent to the flange 9 is prolonged as indicated at 12 to correspond to the prolongation 7 of the channel 5. lVhen the backing 8 is applied to the facing 1 therib 10 is lodged within the channel 5 with the prolongation 12 within the continuation 7 of the channel 5 and the flange 9 abutting the shoulder 4. The backing is united to the the market by manufacturers of such goods.-

It is, however, quite within the ability of the individual dentist to produce the backings, especially when provided with a die or anvil such as is shown and described in Letters Patent No. 1,070,132, granted to meon August 12, 1913, for a method of produclng 'backings for artificial teeth. For thls purpose the dentist provides himself with one or more sheets 14 of suitable metal of appropriate size and this sheet of metal is folded intermediately upon itself as shown in Fig. '2, the foldbeingindicated at 15..

Now, by means of a mandrel and pliers the sides of the folded sheet of metal are brought into close contact leaving the intermediate fold 13 in the form of a tube, as indicated at 15 in Fig. 3. The contacting sides or leaves of the folded together sheet of metal with the tubular mid portion 15*? are now placed in the die and bent away one from the other until in alinement, but with the bends spaced from the tubular portion 15 by a neck 16 indicated in Fig. 4. The sheet 14 is initially of a size so that the structure shown in Fig. 4 is somewhat longer than the rear face 3 of the tooth facing 1. The dentist may now by the use of a file or other suitable instrument cut back the neck 16 from one end to produce a notch 17 seen in Fig. 5. With ajblank resulting from the various steps up to Fig. 5, those portions of the alined sides of the sheet which are now free from any portion of the neck 16, are bent away from the tubular rib 15 to form the flange 9 and that portion of the tubular rib which projects beyond the flange constitutes the extension 12 of Fig. 6 and succeeding figures, while the tubular member 15 then constitutes the rib 10 of the structure of Fig. 6 with the remainder of the neck- 16 constituting the neck 11 of Fig. 6.

, The backing with its locln'ng rib and flange 9 is essentially a one piece structure, being made from the single plate 14 of Fig. 1 and finally worked up into the shape illustrated in Figs. 6 and 7 and shown connected with the tooth facing 1 in Figs. 8, 9 and 10.

When the-backing is applied and cemented to the facing andthe final back coating 13 is applied, the backing '8 is wholly embedded and no portion of the backing is exposed either at or anywhere near the biting edge 2. The result of this is that there is no obtrusive rim of gold, which metal is usually employed for the purpose, at the biting edge of the tooth facing to produce an unsightly appearance or to become dented and oftentimes loosened by use.

A serious objection is found to" bridge,

work where the backing plate is carried to the biting edge of the tooth in that the parts sometimes loosen away from each other at the biting edge and not only is the appearance unsightly, but a very unsanitary condition is produced due to the lodgment of food and other perishable matter between the loosened back plate and the facing even i though the extent of loosening be small.

With the present invention should a tooth facing become damaged it may be divided by a suitable tool along the line of the anchoring rib and be entirely removed from the bridge structure without disturbing the installation of the latter in the mouth of the possessor. The tooth facing of the present There is on the market an alloy known as platinum-silver alloy costing not more than onetenth the price of gold and possessing three or more times the strength of gold, and also being much stifler than gold. With this alloy gold very readily unites. The facility with which the relatively cheap alloy may be substituted for gold in dental -'work.of the character of the present invention permits the dentist to put out superior bridge work at approximately one-third the price of bridge work as ordinarily performed, thus bringing within the reach of people of moderate means dental work which they could not heretofore afford.

,The present invention not only permits the far more economical production ofsuperior dental work, but completely obviates the inartistic' and unsanitary conditions incident to bridge and other similar work where the backingplate is carried to the biting edge of the tooth facing.

What is claimed is A backing for use with a tooth facing having an inset rear face terminating in a lateral shoulder spaced from the biting edge of the facing and with a central longi tudinal anchoring channel opening along one long side toward the'inset face and having the prolongation entering the body of said plate extending from that portion of In testimony that I claim the foregoing the neck remote from the rib in opposite as my own, I have hereto aflixed my signadirections froma mid-line and terminating ture in the presence of two Witnesses.

at one end in a flange ofiset from that face GUSTAV HOLTZ. of the plate remote from the rib and stop- Witnesses:

ping short of the corresponding end of the J OHN H. SIoGERs,

rib. A EDITH'L. BROWN. 

